Transesophageal echocardiography (TEE) has a definitive role in the diagnosis and management of critically ill patients with cardiovascular disease and patients undergoing cardiac operations. The diagnostic role of emergency intraoperative TEE and the impact on clinical outcome have not been evaluated. We reviewed the indications, findings, and impact of emergency intraoperative TEE in 66 patients over a 4-year period. The indications for emergency TEE were unexplained hemodynamic instability (36 patients), preoperative evaluation of patients having emergency surgery (19 patients), cardiac evaluation of trauma cases (6 patients), and unexplained intraoperative hypoxemia (5 patients). New findings were disclosed in 53 (80%) patients, with an alteration of the planned surgical procedure in 15 (23%). Despite the therapeutic impact, 24 patients (36%) did not survive to hospital dismissal. We recommend that TEE be considered as the diagnostic tool of choice when surgical patients have unexplained hemodynamic instability, when time does not permit complete preoperative evaluation, when cardiovascular injury is suspected in a trauma patient, and to evaluate unexplained hypoxemia.